public void Initialize(Activity activity, string serverClientId, bool requestProfile, bool requestEmail)
{
var builder = new GoogleSignInOptions.Builder(GoogleSignInOptions.DefaultSignIn);
if (requestProfile)
{
builder = builder.RequestProfile();
}
if (requestEmail)
{
builder = builder.RequestEmail();
}
if (!string.IsNullOrEmpty(serverClientId))
{
builder = builder.RequestServerAuthCode(serverClientId);
}
googleSignInOptions = builder.Build();
googleSignInClient = GoogleSignIn.GetClient(activity, googleSignInOptions);
Activity = activity;
}